Autoamtic telephone system



Feb. 2, 1960 H. TPFER ETAL AUTOMATIC TELEPHONE SYSTEM Filed Jan. 13,1956 2 Sheets-Sheet l Feb 2 1960 H. 'roPFER ETAL AUTOMATIC TELEPHQNESYSTEM Fied Jan. 1s. 195s 2 Sheets-Shedl 2 United States Patent i@2,923,774 Y AUTOMATIC TELEPHONE `SYSTEM Herbert Tpfer, Munich, andAlfred Scheunert, Berlin- Siemensstadt, Germany, assignors to Siemens &Halske Aktiengesellschaft, Munich and Berlin, Germany, a corporation ofGermany Application January 13, 1956, serial No. 559,015 Claimspriority, application Germany February 2, 1955 11 Claims. (Cl. 179-16)iCC ample of a rectangular path digit suppressor switch; and

Fig. 2 shows a circuit diagram for such switch. `Referring now to thedrawings, characters H and D respectively indicate the vertical androtary magnets. As is apparentfrom Fig. 1, the switch shaft 5 isprovided with a toothed ratchet 2 for executing the lifting or verticalmotion, and with a semispherical toothed 'stepping member 1 forexecuting the 'rotary motion. A pawl 3 controlled by the verticalmagnet-H actuates the vertical ratchet 2 and a pawl 4 controlled by therotary magnet D actuates the rotary stepping member 1. e The steppingmember 1 carries a guide member 8in which are formed comblike recessescorresponding to the decade or level scheme of the contact bank, forcooperation during rotary motion,

witha stationary guide segment 9. Rotary off-normal contacts w12 and w2are provided, such contacts being l actuated responsive to rotation ofthe rotary stepping sameswitch, first in accordance with' apredetermined digit, and thereafter in accordance with another digitdenoting a different traflc direction. For this reason,the switch mustbe released after receiving the first series of impulses, so that it canbe reset iagain responsive to a further series of impulses designatingthe desired traffic direction. Vertical-rotary switches of this type`are sometimes referred to as digit Suppressors or digit absorbers.

`If the corresponding switch is provided with a release magnet, forexample, afStrowger switch, Asuch -magnet' is actuated subsequent to theimpulse series `which is to be suppressed so as to return the wipers tothe` initial position. The release is effected quickly andthe switch isVthen ready to receive the'desired next impulse series. There are,however, switches of the vertical rotarytype'which are released byfurther stepping in the rotary, direction, followed by dropping of theswitch shaft and wipers upon overrunning of the bank contacts in thecorresponding level, and rotation back to initial or normal position,the e wipers going through a rectangular path. In other words, suchswitches are not equipped with special release magnets. The return ofsuch a switch to normal position re.

quires a longer time interval than a Strowger switch, due

to the longer path, through which vthe wipers have toV travel, and thereappears the difculty that the wipers have not reached their normalposition when the next successive impulse series arrives.

The object of the invention is tov effect, in the use of suchrectangular path switches as digit Suppressors, quick restoration intothe normal position. This object is realized byreleasng the verticalmagnet under control of a device which marks the type of the selecteddecade or level, after absorption of an impulse series that is to besuppressed, thereby effecting instant dropping of the switch shaft andwipers into normal position, while keeping the vertical magnet energizedafter absorption of an impulse series which is to be effectively used,for an initial interval-of the rotary wiper motion, thereby preventingthe release operation. A particular advantage of the arrangementaccording to the invention resides in the fact that the correspondingswitch restores to normal position immediately after receiving animpulse series which is to be suppressed, without executing a rotarywiper motion across the entire contact bank, just like knownvertical-rotary switches, for example, of the Strowger type, which are yprovided with special release magnets.

The above indicated and further objects and featuresV member 8. Numeral6 designates a switch wiper, 7 the eld of bank contacts, and numeral 10designates in schematic manner a spring forlrestoring the switch shaft5. The vertical pawl 3'is normally fastened at one end of the armature11 of the vertical magnet H, which is ro tatable about the axis 12. Therotary pawl 4 is carried by the armature 14 of the rotary'magnet D,'suchVarmature being rotatable about the axis 13. vThe vertical pawl 3engages with each attraction of the vertical magnet H a tooth in thevertical ratchet 2, thereby lifting the switch wipers such as 6step-by-step from level to level. An

auxiliary decade wiper ds is at the same time moved vertically withrespect to an auxiliarybank of vertically i disposed contacts. Contacts4k, 2k and 17k are vertical olf-normal contacts which are actuated whenthe vertical ratchet leaves its normal position. The extension 15 of thevertical pawl 3 which engages the teeth'in lthe-ratchet Y member 2 ismade so wide that it remains with attracted armature 11 ofthevertical'magnet H in engagement with a tooth in the lifting ratchet 2until such time whenthe wipers have beenrotavted by two steps. The guide9( forV the wipers are in engagement'with the first bank contacts in aselected level, ythat is, up to the second rotary step, a tooth of thecomb 8 will be in engagement with the guide 9 and the release of theswitch shaft and wipers can be effected only after rotation over allbank contacts in the corresponding level. 5

Fig. 2 shows in schematic manner the circuit of a rectangular pathswitch operating as a digit suppressor, con- A structed in accordancewith Fig. 1, illustrating the circuitry for controlling the switchoperations to the extent required for an understanding of the invention.

When the switch is seized by a preceding switching device, line. relay Awill be energized over line conductors a and b and test or seizure relayC will energize in a circuit involving the private conductor c, verticalolf-normal contact 2k and a resistor to battery (e), the shunt aroundrelay C being removed by the opening of contact 1a controlled by relayA. Relay C upon operating closes its contact 3c, thereby'shu'nting theolf-normal contact 2k, and closes at contact 5c a circuit for relay Jextending from vertical olf-normal contact 4k, contact 5c, winding II ofJ, rotary off-normal contact w12, contact 6d of the rotary magnet,winding I of I to Now, when the rst impulse series arrives, relay A willfollow and upon deenergization will open contact 7a to Patented Feb. 2,1960 remove the shunt around relay V whose energizing circuit wasprepared over contact 8c upon actuation of relay C. Relay V accordinglyenergizes and at contact 9v closes a circuit for the winding III ofrelay I. Relay A energizes again. atthe conclusion of the first impulse,thereby closing at contact 10a a circuit for relay B extending overclosed contact 9.v,vrelayV B closing a circuit forv the vertical magnetH from H, 1-1v, 12b, rotary oifnormal contact w2, 13p to. The verticalmagnet H operates and by means of its pawl 3L, 15- i) lifts the ratchet`2 and therewith the wipers 6 by one step. Relay B releasesuponrestoration of relayv A at the beginning of the next impulse andconsequent opening of contact lila, interrupting the circuit of thevertical magnet H at contact 12b. Upon conclusion ofthe irnpulse, relayB and therewith the vertical` magnet H are reconnected. Relay V remainsenergized during each impulse series because it is made slow-to-releaseby the periodic shunting of its winding atrcontact 7a; it releases upontermination. of the impulse series,` causing the nor mal contacts ll-vto close and thereby connecting the vertical magnet H (which had beenenergized over contact 12b) with thev decadeor level wiper ds of theswitch. If the decade wiper has been setr by the received impulse seriesin engagement with onefof the contacts corresponding to decades orlevels 1 kto 8 in Vwhich no` Suppression is intended, the verticalmagnet H will remain energized over low ohmic resistor Wi and contacts4Mc, W2, 13p. Relay J has been energized upon release of relay V overcontacts iSv and 161', in a circuit over vertical off-nor mal contact17k whichV became closed responsive to thc iirst vertical step, toground at contact 13p. At contact 181', relay I connects the circuit forthe rotary magnet D. This magnet interrupts at'contact 6d the circuitfor relay I causing release thereof and the latter opens contact 181disconnecting the rotary magnet. Contact 6d is accordingly closed againcausing relay I to reenergize over winding I in a circuit includingcontact 19h controlled by the vertical magnet H. Relay J at contact 18x"reconnects the Vrotary magnet causing the switch to execute a secondrotary step. The rotary olf-normal contact w2 is coincidently 'switchedto alternate position interrupting the holding circuit for theverticalmagnet. Since a tooth of the guide comb 8 is now in'engagementwith the guide 9, restoration of the'switch wipersv to normal or homeposition will require, as explained before, further rotation thereofbeyond the last bank contacts in the corresponding level, thereupondropping of the shaft and wipers, and finally return rotation to normalposition. In other words, rapidV restoration, is now impossible. Theinterplay between relay i and the rotary magnet D continues, in thecircuit over Contact W2 until bank contacts associated with an idle lineor trunk leading to a succeeding switch are found which is ascertainedover the test or private wiper wc. When an idle line is found, windingsI and II of test relay P will receive current over contacts 20c and 21dor 22x' and relay P will energize. At contact 13p, relay P interruptsthe circuits for relay J and the rotary magnet D, thus stopping theswitch. Closure of contact 23p shunts the high resistance winding II ofrelay P for the purpose of busying the seized line or trunk. At`contacts 24p and 25p, relay P connects the line conductors through tothe succeeding switch.

However, if the first digit received should be the number 9 or 0 (digitsto be suppressed), the switch wiper cis, upon conclusion of thecorresponding impulse series will be in engagement with one of thecorresponding topmost decade contacts, and. the winding of relay F willbe energized responsive to release of relay V. Relay F closes itscontact 2,6]1 in a holding circuit for its winding I. This winding has ahigh resistance, causing release ofthe vertical magnet H, and therebydisengagement of the extension 1S of pawlV 3. (Fig. 1)v from the ratchet'Ehe switch has meantime as previously described executed one rotarystep but the comb 8 is not in engagement with the guide 9. The switchshaft 5 and therewith the wipers accordingly drop quickly into normalposition and the switch is thereby prepared for renewed operationresponsive to receipt of a further impulse series. Vertical oinormalcontact 4k is in the normal switch position closed again and thewindings II of the relays J and F are accordingly energized in parallelover contact 27fi which also closed upon operation of relay F over itswinding I. Contact ZSH of the second switching stage is now closedassuring continued energization of the vertical magnet H over the lowohmic resistor Wi responsive to the next impulse series, independent ofthe position of the decade wiper ds, until such a time when the rotaryoff-normal contact w2 opens. Prolonged energizationV of theA verticalmagnet H thus prevents immediate release of the switch. Accordingly,even if the corresponding impulsey series should denote digit 9 or 0,rapid release of` the switch by deenergization of vertical magnet Hcannot take place.

The invention is not inherently limited for use in telephone switchingdevices andl the corresponding term is accordingly intended to embracedifferent signaling systems in which the invention can be used.

Changes may b e made within the scope and spirit of the appended claimsvwhich define what is believed new and desired to have protected byLetters Patent.

We claim: y

1. InV an automatic telephone system, anV automatic switch of thevertical-rotary type having a verticall magnet for lifting a shaftcarrying wipers, responsive to impulses received, to position saidwipers for rotation relative, to a desired level of bank contacts, andhaving a rotary magnet for rotating said shaft so as to rotate saidwipers relative to the bank contacts in the corresponding` level,wherein the release andy restorationv of said Vwipersis effected byrotation thereof beyond the last bank vcontacts in the correspondingvlevel, thereafter dropping` of said shaft andl said wipers to lowermostposition, followed by return rotation thereofV to normal, a device foradapting said switch for operation as a digit suppressor, said devicecomprising, decade markerV means,- circuit means for conductingdigit-designating4 impulse series to saidswitch to cause operation ofsaid vertical magnet, circuit means controlled by said marker meansresponsive to, receipt of digit impulse series to be suppressed forcausing immediate release of said vertical magnet to restore said switchwipers to normali, and fur ther circuit means for causing said verticalmagnet responsivc to receipt of a digit impulse series to be effectivelyused `to remain energized for the initial interval of the operation ofsaid rotary magnet by the next successive impulse series, therebypreventing immediate release of said switch.

2. An arrangement and' cooperation of partsA according to claim 1,comprising two resistors, switching means which is operatively effectiveat the conclusion of an impulse series, and circuit means controlled bysaid relay and said marker means for connecting said resistors in thevcircuit of said vertical magnet.

3. An arrangement and cooperation of parts according to claim 2,wherein` one. of said resistors has a relatively low resistance.

4. An arrangement and cooperation of parts according to claim 2, whereinone of said resistors has a` relatively high resistance.

5. A n arrangement and cooperation of parte according to claim 4,comprising a relay having a winding constituting one o f said resistors,and circuit means controlled by said relay responsive to` said' switchassuming normal position and reoperation thereof for connecting saidsecond resistor which has a relatively low resistance in the circuit ofsaid vertical magnet independent of saidk marker means.

6. An. arrangement andv cooperation of parts according to claim 5,wherein said relay operates in stages, circuit means for operativelyconnecting one winding of said relay to actuate such relay in its rststage after receipt of an impulse series to be suppressed, means forthereby preparing a circuit for a second winding of said relay, andmeans effective upon return of said switch to normal position forclosing said last-named circuit for the actuation of contacts in thesecond stage of said relay.

7. An arrangement and cooperation of parts according to claim 3,comprising a holding circuit for said vertical magnet including saidresistor having low resistance and a rotary off-normal contact which isopened responsive to rotary operation to the second rotary step of saidwipers.

8. An arrangement according to claim 2, comprising an auxiliary relayfor operatively connecting said vertical magnet, a line relay responsiveto impulses received for actuating said auxiliary relay for the durationof the pause between two impulses, and a switch-over relay for actuatingsaid auxiliary relay upon conclusion ofan impulse series for an intervaluntil said vertical magnet is connected to said marker means.

9. An arrangement and cooperation of parts according to claim 7, whereinthe wipers of said switch engage live bank contacts responsive to thesecond rotary step thereof.

l0. An arrangement and cooperation of parts according to claim 1,comprising a lifting pawl controlled by said vertical magnet forcoaction with a corresponding lifting ratchet, the operative end of saidpawl being wide enough to remain in engagement with said ratchet inexcess of one rotary step of said rotary magnet.

11. An arrangement and cooperation of parts according to claim 10,comprising a stationary guide element, and a switch shaft carrying aguide comb for engagement with said guide element in the second rotarystep controlled by said rotary magnet.

References Cited in the tile of this patent UNITED STATES PATENTS1,694,615 Bellamy Dec. 11, 1928 2,236,808 Taylor` Apr. 1, 1941 2,513,400Carson et al. July 4, 1950 2,820,101 Pharis Jan. 14, 1958

